Zoom-up star photos poke holes in century-old astronomical theory

April 18, 2011

An image of the star Regulus, which University of Michigan astronomers and their colleagues were able to "zoom in" on using a technique called interferometry. Zooming in allowed them to measure the temperature of the star's poles separately from its equator, which enabled them to find flaws in a century-old astronomical theory about hot, fast-spinning stars. Credit: Xiao Che

(PhysOrg.com) -- The hottest stars in the universe spin so fast that they get a bit squished at their poles and dimmer around their middle. The 90-year-old theory that predicts the extent of this "gravity darkening" phenomenon has major flaws, according to a new study led by University of Michigan astronomers.

The von Zeipel law, named for its creator, Swedish astronomer Edvard Hugo von Zeipel, has been used for the better part of a century to predict the difference in surface gravity, brightness and temperature between a rapidly rotating star's poles and its equator.

Using a technique called interferometry the researchers essentially zoomed in to take close-up pictures and measurements of the winter star Regulus. It's the brightest star in the constellation Leonis and if it were spinning just a few percent faster, it would fly apart.

The astronomers found that the actual difference in temperature between its equator and poles is much less than the old theory predicts.

"Our model fitting of interferometry data shows that while the law correctly describes the trend of surface temperature variation, it deviates quantitively," said Xiao Che, a doctoral student in the Department of Astronomy who is first author of a paper on the findings to be published in Astrophysical Journal on April 20.

"It is surprising to me that von Zeipel's law has been adopted in astronomy for such a long time with so little solid observational evidence."

It's important to get this number right, says John Monnier, an associate professor in the U-M Department of Astronomy.

"In some cases, we found a 5,000-degree Fahrenheit difference between what the theory predicts and what our actual measurements show," Monnier said. "That has a big effect on total luminosity. If we don't take this into account, we get the star's mass and age and total energy output wrong."

Monnier led the creation of the Michigan Infra-Red Combiner (MIRC) instrument that was used to take the measurements that led to this discovery. MIRC uses interferometry to combine the light entering four telescopes at the CHARA array at Georgia State University so that it seems to be coming through a device 100 times larger than the Hubble Space Telescope. The technique lets astronomers see the shape and surface characteristics of stars. Previously, stars were mere points of light even with the largest telescopes.

In this case, zooming in on Regulus let the researchers measure its poles and equator temperatures separately.

"Normally, you would just be able to get an average temperature," Monnier said.

So where did von Zeipel go wrong? Monnier believes his Swedish predecessor didn't take into account circulation on stars that's not unlike wind patterns on Earth.

"The Earth has a hot equator and cold poles and that causes air circulation," Monnier said. "The hot air wants to flow toward the poles and equilibrate, bringing the temperatures closer together. This is a source of some weather patterns on Earth."

[B]Researchers take picture of the face of Altair, a first for a star like our own[/B]
Using a suite of four telescopes, astronomers have captured an image of Altair, one of the closest stars to our own and a fixture in ...

(PhysOrg.com) -- Astronomers using the W. M. Keck Observatory have peered far into a young planetary system, giving an unprecedented view of dust and gas that might eventually form planets similar to Jupiter, Venus, or even ...

For astronomers, it's always been a source of frustration that the nearest white-dwarf star is buried in the glow of the brightest star in the nighttime sky. This burned-out stellar remnant is a faint companion of the brilliant ...

Astronomers generally assume that the dusty disks where planets form are found around young stars in stellar nurseries. Now, for the first time, a planet-forming disk has been found in the environment of a dying star.

The observation of the immediate vicinity of a star other than the Sun has just been carried out for the first time. A debris disc made up of hot (1300 degrees) dust grains, residues of comet evaporation and collisions between ...

The constellation of Virgo (The Virgin) is especially rich in galaxies, due in part to the presence of a massive and gravitationally-bound collection of over 1300 galaxies called the Virgo Cluster. One particular member of ...

(Phys.org)—A small team of researchers from the U.S. and Italy has found evidence of a naturally formed quasicrystal in a sample obtained from the Khatyrka meteorite. In their paper published in the journal Scientific Reports, ...

As a cosmic dust magnet, Saturn's C ring gives away its youth. Once thought formed in an older, primordial era, the ring may be but a mere babe – less than 100 million years old, according to Cornell-led astronomers in ...

52 comments

It is surprising to me that von Zeipel's law has been adopted in astronomy for such a long time with so little solid observational evidence.

One can say the same about a lot of "accepted" things: the formation of the planets comes instantly to mind - things that would normally smash and bounce off each other suddenly clump together to form planets.The Oort cloud - has it ever been seen? NOPE. I can go on.

Yep. You've certainly proven that. And I will point out YET AGAIN, that when someone comes up with a VALID criticism of some scientific item, it's always a SCIENCE-based criticism. That's because science, unlike superstition, checks and rechecks and rerechecks its facts, and tosses stuff out when it fails to match observations. Unlike theistic fantasies, where you just huff and puff and point to the bible and howl louder.

ZephirAWT

the formation of the planets comes instantly to mind - things that would normally smash and bounce off each other suddenly clump together to form planets.

Accretion was confirmed by all observations obtained in experiments run by the various Apollo mission crews.

The Oort cloud - has it ever been seen? NOPE. I can go on.

Inference is evidence.

I claim that you killed someone yesterday at noon. You provide records that distinctively prove you were elsewhere at the time. No one in court saw you elsewhere, but the data conclusively shows that you were not at the scene of the crime. Should you go to jail? Your comment above implies that you should.

It is surprising to me that von Zeipel's law has been adopted in astronomy for such a long time with so little solid observational evidence.

One can say the same about a lot of "accepted" things: the formation of the planets comes instantly to mind - things that would normally smash and bounce off each other suddenly clump together to form planets.The Oort cloud - has it ever been seen? NOPE. I can go on.

Without physical evidence, once can only go on what data they have. New data came to light (literally) and they updated their knowledge (or, in this case, their accuracy). Where's the problem? Show me where this self-scrutiny and correction is done in religion? One group constantly strives for truth by testing and updating, the other just presumes the first ideas were 100% right with zero testing. Which group holds more credibility?

kevin, again I ask: If the universe were created thousands of years ago, why can we see objects BILLIONS of light years away?

things that would normally smash and bounce off each other suddenly clump together to form planets.

Do you even read the replies to your posts? Or do you do drive-by postings, never to return and read the replies, because this has been responded to (by myself, just a couple of days ago in another thread) as well as by others.

He never responds to the "when was the flood" questions from Ethelred. I've asked him to explain geologic layering and why we don't see the sediment increasing by 18 inches per year.

I used to wonder why people like him waste their time here. I don't care as much anymore. Actually, with the billions of internet capable people around the world, I'm kind of surprised there aren't more people like Kevin on these threads.

I still wonder that. It *can't* be because he thinks he's convincing people of anything, not with the way he constantly gets squashed. He couldn't be that stupid and still know how to use a keyboard. It *has* to be simple trolling. Maybe he likes to "rile up the atheists" and probably gets some kind of feeling of pride out of that. If so, pretty sad.

His examples of things that are accepted despite a lack of observational evidence were poor examples, but there are plenty of good examples.

Just look up all the things people used to believe which we now know are not true, thanks to observations we can make now. The flat Earth is an old one. It's hard to say which of today's strong theories might be overturned in the next decade, but there are lots of them that exist without very much observation. For example, the composition of the Earth's interior is one field where observation is very limited. They may be 100% correct, but we don't really know for sure. Mass extinctions of the past are good ones, as well as the start/end of ice ages. I seem to recall people saying that there was no water on the moon a couple decades ago. The interior of Titan is a good example too. If you're doing science on something where the answers are already known and there's plenty of observations to back the theories, then are you really doing science?

An example of something that is theorized without observation doesn't need to mean that it is disproven by later observations either. Memristors, superconductors and fission bombs are examples of things that were predicted by theory but were not confirmed by observation until later. Subatomic particle physics is full of such examples.

Here's a recent example where observations contradict long held theory:

I think that those examples where we thought something to be true, that was later turned over by further investigation are WONDERFUL. They show exactly why science offers people like me a much stronger framework on which to build my world view.

Science Admits that it might not have everything 100% correct, and constantly searches for the areas where it is not perfected. When an error is found, it is corrected, Ideas don't stick around just because it was written in some old book.

Science Admits that it might not have everything 100% correct, and constantly searches for the areas where it is not perfected. When an error is found, it is corrected,

I wonder how many ministers/priests/pastors, etc say different on the pulpit. I've seen some pastors say some pretty crazy stuff, so I can only assume they bad mouth science from time to time. Once, an Army Chaplin at a "Charismatic Service" talked about curses and demons as if they were real physical objects floating around us. His theory was that "curse" words literally create demons out of thin air (or pull them from hell) where they float around and do damage to everyone in the vicinity. I mean, really? Is there even any biblical support for this? (edit: yep. sheesh)

He never responds to the "when was the flood" questions from Ethelred. I've asked him to explain geologic layering and why we don't see the sediment increasing by 18 inches per year.

I used to wonder why people like him waste their time here. I don't care as much anymore. Actually, with the billions of internet capable people around the world, I'm kind of surprised there aren't more people like Kevin on these threads.

Note that kevinrts is clearly violating the comments guidelines against posting religious or pseudoscience.

His theory was that "curse" words literally create demons out of thin air (or pull them from hell) where they float around and do damage to everyone in the vicinity.

What kind of stupid fucking shit is that? Oops...... help, they're all around me, they're hideous and damaging, apparently!

But seriously, didn't "Southpark" do an episode like that where curse words caused people to die from the plague or something? That show is really spot on with some of its social commentary.

My favorite moments are when Christians tell you something crazy out of the blue with no warning and they say it as a matter of fact. Once my father in law said something really "normal" about the bible and immediately followed it with "you know, there were giants in those days". One of the few times I've been speechless. He had a perfect delivery, sincerity with direct eye contact. I don't quite remember how I dealt with that. I think my look said it all.

But seriously, didn't "Southpark" do an episode like that where curse words caused people to die from the plague or something? That show is really spot on with some of its social commentary.

That was a good one. They had a ticker on the bottom corner counting how many times anyone said 'shit'. I looked it up. 162 times. The title was "It Hits the Fan" episode 66. 66 huh? Coincidence? I think not.

"you know, there were giants in those days".

I am amazed by how much crap people just believe with no thought or investigation. It's as if most people just don't care at all what is true or not. I'm not limiting that to mainstream religious, either. Almost everyone I know that is roughly my age (low 30s) has their own special brand of spirituality with no bearing on reality whatsoever. 5 times in the last week I heard a dear friend say "Everything happens for a reason." I don't want to be that A-hole, so I just let it go.

Just look up all the things people used to believe which we now know are not true, thanks to observations we can make now. The flat Earth is an old one.

Um, wow. Wrong. We actually have zero evidence that any scientific community at any point in earth's history believed the earth was flat. We DO have evidence that we have known it's (roughly) spherical since at least a thousand years B.C.E. The whole flat-earth idea is just an urban legend.

His theory was that "curse" words literally create demons out of thin air (or pull them from hell) where they float around and do damage to everyone in the vicinity.

What kind of stupid fucking shit is that?

Oh, yeah, sorry, one more. His sermon was on the Sunday before Halloween and he was warning his parishioners not to take part. He and his congregation also believed Lord of the Rings and Harry Potter movies were evil and were not to be watched.

5 times in the last week I heard a dear friend say "Everything happens for a reason." I don't want to be that A-hole, so I just let it go.

Sorry for the off topic vent.

Not at all, it's good to vent this kind of stuff. I did the opposite with my wife when she asked if I thought we were soul mates. I actually told her that I believed that two people could have the highest compatibility defined by some metric, but that the likelihood of us meeting would have been astronomical. I do believe that two people become "soul" mates after they fall in love for a long time. I now feel that she is in fact the perfect person for me. We have both adapted to suit each other and I believe that our neural pathways have actually rewired over the years to mesh perfectly. We are no longer who we were when we met and we have become dependent on the existence of each other. In a way, I think that is almost more moving. She thought so too.

I'm not too familiar with the poster that has drawn so much scorn, but it should be apparent that many of the currently accepted models are false.In addition, the idea that someone criticizes the current religion of science, is in some way unscientific or has to be promoting some parallel religion is nothing but a strawman.Likewise the use of isolated examples of extreme fundamentalist rhetoric to damn all religious people and their leaders is nothing but the most extreme ignorance.There is and always has been religious men and women who are also scientists, and the truly enlightened see no problem what so ever with integrating science and religion.So, it apprears as if all those criticizing the OP are guilty of violating the terms of the guidelines.Now I know that I'll recieve hateful responses for crticizing your religion, but yours is no different from the OP.Wake up children and get a clue.Our science has virtually zero direct observation of the vast majority of the universe

It's not trolling, they genuinely need to fight to retain the illusion that a world view founded by a book written thousands of years ago is a true view of reality. Until you understand they are quite literally deluded in a pathological way you will try to communicate with them as if they are rational.

Any evidence of an incorrect model coming from the world of science they will leap on and irrationally, but genuinely, think that this gives their view of reality more credence (a rational mind knows there is no correlation).

You cannot break through that irrational wall without understanding them on a personal level to gain insight into why they must fight so hard to retain the delusion... usually it is due to family or social reasons... very important things for the social animal we are.

and the truly enlightened see no problem what so ever with integrating science and religion.

False. Truly enlightened men are aware that there is no evidence for a god at the moment, and even if there was such evidence, assuming godidit instead of actually finding out how things occurred is completely counter to the idea of finding out how the universe really works. Which is what science is about. How does things work. How did the world come to be the way it is. If you don't look then you are not doing science.

So, it apprears as if all those criticizing the OP are guilty of violating the terms of the guidelines.

No. That is another lie. Kevin makes religious posts that are contrary to facts most of the time he posts. The key there is CONTRARY to REAL evidence.

Now I know that I'll recieve hateful responses for crticizing your religion,

I don't hate you for telling lies. I just point out that they ARE lies.

Child, I have a clue. I have a whole Universe telling me that Kevin is wrong. If Kevin was right we could not see another galaxy and we can. If Kevin was right there would evidence of a world wide flood everywhere we look on Earth. From the highest mountain to the DNA of all life on Earth it would be clear that the world had a devastating killing event. There is no such evidence.

Our science has virtually zero direct observation of the vast majority of the universe

Nonsense. Typical lie by a Creationist that is wholly ignorant. Astoundingly ignorant for someone that joined this site in 2007.

and the theories that it uses to explain what it can see are being disproved almost daily.

Lied again. The theories are backed up every day. The theory in this article was a minor theory from so long ago it is strange that anyone was still using it since it was from before fusion was understood. Using it was rather like using Lord Kelvin's work on the Sun. Totally obsolete. Present day theories are usually pretty good matches to what we actually see with much better instruments.

So, how about YOU answer the question that Kevin runs from. Maybe YOU have more guts than Kevin.

When was the Great Flood? How do you reconcile the Biblical derived date with Egyptian and Sumerian history?

This is so funny. I've been around here for years now and most of the religious oriented posts here are from Christians. I live in a part of the planet where most people have many many gods and many many ancient texts to quote from. Most of these old texts were written ridiculing or "correcting" previous ones. So, one can fit in just about anything that's discovered by science to correspond to some verse somewhere in some text! Therefore, the problem people like me face where I live is just the opposite to what people like me face here: The standard thing that one hears in my part of the world is,"Of course it is so! It has always been there in (some xyz ancient book)." And then they point out a co-relation. Sigh!

but it should be apparent that many of the currently accepted models are false

Such as? And, back it up with WHY it's "apparent"?

the current religion of science

Religion is the blief in something without proof or evidence "faith". Science is the logical study of observational phenomenon with the extension of LOGICAL theories to explain them (as much as possible, based on things that can be tested). Therefore, by definition, science is NOT a religion.

is nothing but a strawman

Please explain how it's a "strawman". We're all familiar with the strawman argument, so please explain how our response to kev's direct statements are "strawmen".

Tell me: What IS my religion? Back up your presumption with proof or retract your statement and apologize.

Our science has virtually zero direct observation of the vast majority of the universe

What are you talking about? Be SPECIFIC.

theories that it uses to explain what it can see are being disproved almost daily

Newton's laws of motion? The laws of thermodynamics? General and Special relativity? Quantum physics? The 4 forces of nature?None of those have been disproven since they arrived and those are the fundamental building blocks of most of scientific knowledge. They get tweaked every now and then, but not disproven.

The old theory in this article was not bad considering he didn't have the knowledge we have today. His theory was updated with more accurate measurements and knowledge. Show me where this is done as a common practice in religion?

I'll ask you the same question I've asked Kevin multiple times with absolutely no response whatsoever:

1. If the universe is only thousands of years old, why can we see objects BILLIONS of light years away?2. Same question Etherlred asks: Was there a global flood? When? Where's the evidence? Why didn't the Egyptions notice? Where'd the water come from? Where'd it go? Provide something other than "it was magic" or "well, this old book, written a long time ago, says X".

And again:

3. What do you think MY religion is? Back it up with evidence. When you're wrong, I do expect an apology.

You talk ill of "science", yet you use science yourself in your arguments (poorly, yet you do it). What do I mean? I mean, you're trying to link ideas together with logic and reason. THAT IS SCIENCE! And the practice of using logic and reason (a.k.a. "science") is NOT a religion; it's a fundamental requirement of basic thought. Even animals do it.

Sometime back I had this conversation on line with a person who insisted that all was created 6000 years ago. I asked the question: Why can we see galaxies billions of light years away?His answer: "God created the light in transit to confuse the mind of the nonbeliever."Then I pointed out that a supernova can seen the same billions of light years away, meaning that that star was destroyed before it ever existed. Then I asked him, "Are yousuggesting that God is a practical joker?"His response to that: "I don't want to talk to you anymore."

It is surprising to me that von Zeipel's law has been adopted in astronomy for such a long time with so little solid observational evidence.

One can say the same about a lot of "accepted" things: the formation of the planets comes instantly to mind - things that would normally smash and bounce off each other suddenly clump together to form planets.The Oort cloud - has it ever been seen? NOPE. I can go on.

But please don't. Because you're wrong. You mention one thing that we will never be able to directly measure, and another that we are currently not able to. A lot of thought and study has been put in to come up with our best guesses, and that's what they are. Certainly they are more informed guesses than your opinion.

The observer observes that the believer believes despite and/or because of missing evidence.The observer is not the believer.

So what was the point of your initial statement? He said the truly enlightened have no problem with mixing religion and science and I pointed out that was NOT enlightenment because mixing the two is contrary to scientific thinking.

I did NOT say a person could not be a scientist and religious. I have never said such a thing.

But you CANNOT do honest science if you assume the answer is goddidit. Stillwind's reply seemed to be a rejection of that. Based on his statement Dr. Behe should be considered good and proper scientist when he is a really poor one outside his own field. Which is not evolution.

See the article that only Oliver cites. See the article the original does NOT cite. See the article the original author was clearly spitwadding in and has not written anything to support.

He does NOT support you Oliver. He gave up on that silly idea. Go ahead. Show where he supports your thinking. At any time since that he wrote that. It was preposterous then and even more so now that we know so much more about pulsars. 1977 is a LONG time ago.

Same thing. At least in this case. The assumption that goddidit is contrary to doing good science because it assumes there is no other answer possible.

Again, it boils down to semantics. Integrating is not mixing.

It is not mere semantics. It is not science. It IS religion to assume goddidit so don't look. Which is what Dr. Behe does to give an example that is very relevant to any such discussion.

AGAIN I have NEVER said a person could not be religious and do good science. I said good science cannot be done if you assume there is no answer except a religious one. Which is clearly what stillwind is advocating. Otherwise he wouldn't have been calling science a religion.

Same thing. At least in this case. The assumption that goddidit is contrary to doing good science because it assumes there is no other answer possible.

Not really. Some religious figures in physics, namely Max Planck, Erasmus Darwin, etc used their religious conviction to drive their want to understand 'how god did it'. You can be a religious scientist, you can be a scientific religious person, to be either you only need to not go on assumptions.